During the manufacture of tufted products, such as carpet or turf, a roll of primary backing material can be supplied from a supply roll and continuously fed through a tufting machine. The tufting machine can be provided with a reciprocating needle bar having a series of spaced tufting needles disposed on the tufting machine for insertion of tufts into the backing material. Due to the inherent ability of backing material to stretch, the tension in the backing material naturally varies during operation of the tufting machine based on the weight of the backing material present on the roll at any given time. For instance, as the roll of backing material gradually decreases in diameter, the tension across the backing material also decreases. As can be appreciated by one of ordinary skill in the art, different types of backing materials have different corresponding tensile strengths, and as a result, the tension can also vary with the type of backing material used. Such changes in tension can create backing wrinkles (pleats), stitch rate and stitch density variations, pattern variations, and measurement errors, leading to increases in waste and manufacturing costs while simultaneously causing decreases in quality and customer service.
Previous systems and methods have attempted to pre-stretch a primary backing material as it is fed into the tufting zone of the tufting machine such as through use of a spiked roller connected to a gearbox/motor combination, which controlled two primary backing rolls at the same time by setting a resistance on a potentiometer. However, such systems and methods are ineffective at maintaining tension in a backing material being fed to a tufting machine, particularly for those processes requiring more than one type or layer of primary backing material.
Thus, there is a need for systems and methods that eliminate or reduce the backing wrinkles (pleats), stitch rate or stich density inconsistencies, pattern variations, and measurement errors associated with existing processes for manufacturing tufted products, particularly tufted products having multiple backing layers.